Here's a plug for a great online community that I like, YALITCHAT.
The people are great, You don't have to worry about vicious posters trying to prove how clever they are.
Also, the Groups (categories) are very helpful: Synopsis Repair Shop, Writing Contests, Query Kick-Around, Crit Seekers, etc.
Georgia does a nice job of keeping things running smoothly.
Create your own page kinda like Facebook, then jump in. That's what I did.